Staybolt installation for steam-boilers



J. R. FLANNERK' STAYBOLT INQTALLATION FOR STEAM BOILERS.

' APPLICATION FILED AP 0 9 l 9. 1,364,097, Patented Jan. 4, 1921.

gwlmmm JOHN ROGERS FLANNEBY, OF PITTSBURGH, YENNSYLVANIA, ASSIGNOR TO FLAN- NERY BOLT COMIANY, OF PITTSBURGH, PENNSYLVANIA.

STAYBOLT INSTALLATION FOR STEAM-BOILERS.

Application filed. April 30, 1919. Serial T 0 all 10 ham it may concern.

Be it known that I, Joni Roonns FLAN- nnnr, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improve ments in Staybolt Installation for Steam- Boilers; and 1 do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements iirthe installation of staybolt structures in boilers.

In the installation of staybolts in a boiler construction, between the inner or fire box sheet and the outer sheet, it is important that a degree of clearance shall be provided between the rounded head of the staybolt and its hearing, which clearance shall compensate for the initial unequal expansion of the boiler sheets.

In practice, when firing up a locomotive boiler, the fire box formed by the inner sheet will expand more rapidly than the outer shell in a diagonal upward direction. As steam is raised to the point of working pressure, the outer boiler sheet will expand in its relative course extending longitudinally in greater proportions. The difference in the amount of expansion between sheets varies with different types of boilers, but the clifference in the amount of expansion and the consequent amount of clearance necessary for the heads of the staybolts to compensate for such difference in expansion, may be determined by experiment for each type of boiler.

One object of my invention is to definitely provide, at the time of installation of boiler staybolts, for clearance between the bolt heads and their seats or bearings to compensate for the subsequent initial difference in expansion between the boiler sheets, and thus avoid the necessity of relying upon the uncertain accuracy of effecting adjustment of the bolts by turning them backwardly to move their heads away from the seats which said heads will subsequently engage.

With this and other objects in view, the invention consists in certain novel features as hereinafter set forth and pointed out in the claims. H

In the accompanying drawings, Figure 1 Specification of Letters Patent.

Patented Jan. 4, 1921.

is a view illustrating an embodiment of my invention, and Fig. 2 is a View showing the application of my invention in a staybolt structure of the type employing a bearing sleeve and cap thereon.

1 represents an outer boiler sheet or a roof sheet having a bolt hole and a concave or partly spherical seat 2, which latter may be reamed, or otherwise formed, for the rounded head 3 of a staybolt a, the inner end of the staybolt being threaded through the inner or fire-box sheet and upset.

In installing the bolt, I place a ring or washer 5 on the seat 2 so that when the staybolt is passed through the hole in the outer boiler sheet and secured to the inner boiler sheet, said ring or washer will be disposed between the curved bearing portion of the head of the bolt and the seat 2. The ring or washer 5 is composed of material which will be dissolvable by water or which shall be softened by contact with water and therefore be destructible. As one example of material of which said ring or washer may be made, absorbent paper may be mentioned. The ring or washer constitutes a destructible compensating member which serves as a spacer between the bolt head and its seat during the initial installation of the bolt in the boiler, and its thickness will be such as to provide, when destroyed, a clearance between the bolt-head and its seat substantially equal to the difference in degree of expansion between the boiler shees when the operation of the boiler is started after the installation of the bolts shall have been completed.

After the staybolts shall have been con.- nected with the boiler sheets in the manner above explained, the rounded head of each staybolt and the opening in the outer boiler sheet in which said head is mounteu, are covered and inclosed by a cap 6, secured to the outer boiler sheet by welding. In effecting the welded connection of the cap 6 to the boiler sheet, the peripheral edge of said cap may be beveled as at 7 and this beveled edge is united to the outer face of the outer boiler sheet with the use of a welding alloy, thus forming a weld, as indicated at S. The cap 6 may be made with an opening 9 through which access may be had to the head of the staybolt, and this opening will be normally closed by a threaded cap or plug 10. If desired the cap or plug 10 and the ployed, the destructible member opening 9 in the cap 6 which it closes may be omitted. V

In Fig. 2, is shown the application of my improvements to a type of staybolt structure in which a bearing sleeve 11 is em- 5 being dis posed between the head of the seat 12 therefore in said sleeve. A cap 13 constitutes a closure for the sleeve and is formed with a flange 14 threaded on said sleeve.

When the st-aybolts shall have been i11- sta-lled in the boiler and the caps or closures shall have been applied over the heads of the bolts and over the openings through which the bolts pass, the operation of the boiler may be started. hen the water or moisture reaches the destructible spacing member 5, it will soften the same and finally result in its destruction, (the latter being hastened by the movements of the bolt and the boiling of the water), thus providing a clearance between the bolt head and its seat which will compensate for the movements, by expansion, of the boiler sheets.

Having fully described my invention bolt and the what I claim as new and desire to secure by Letters Patent, is zy 1. The herein described method of compensating for the initial difference in expan- 3 sion between boiler sheets relatively to staybolts connecting them, consisting in securing the staybolts to the inner boiler sheets,

and in initially spacing the head of the bolt from its seat withmaterial which shall be 3 destructible by moisture.

2. In a staybo'lt' structure, the combina tion with boiler sheets, a staybolt connecting them, a head at the outer end of said staybolt, and a seat at the outerboiler sheet for 4 said head, 01 a temporary spacing member destructible by moisture or steam disposed between the head of the staybolt and its seat at the outer boiler sheet; 7

In testimony whereof I have signed this 4 specification in the presence of two subscribing witnesses.

JOHN ROGERS FLANNERY.

Witnesses V JOHN M. RONEY, JAs. R. HORAN. 

